Abstract

The interaction of oxygen atoms with three types of plasma enhanced chemical vapor deposition low-k SiOCH films is studied. The samples were treated by O atoms in the far plasma afterglow conditions in a special experimental system designed for this study. The experimental system allowed avoiding the effect of ions and vacuum ultraviolet (VUV) photons on surfacereactions and controlling the oxygen atom concentration over the samples. Fourier-transform infrared spectroscopy, x-ray fluorescence, and atomic force microscopy techniques were used to analyze the changes occurring in low-k films. Monte Carlo model for O atom interaction with low-k material that includes penetration, recombination, and reactions with methyl groups was developed. It is shown that the surface recombination on the pore wall surface determines the profile and penetration depth of O atoms into the films. The reaction of O atoms with methyl groups has lower probability and therefore proceeds in the background mode.

Received 05 May 2010Accepted 04 August 2010Published online 11 October 2010

Acknowledgments:

This study is carried out in the frame of MSU-IMEC Agreement and was supported by RFBR under Grant Nos. 09-02-01374-a and 08-02-00465-a, Key Science School (Grant No. SS-3322.2010.2), and Russian Government Grant No. 02.740.11.0235.